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I want to reveal a few exciting things that are just over the horizon.

Firstly, I will be featured in an article in July’s addition of Delicious. Magazine – one of the UK’s top foodie mags. The article is a step by step guide on, you’ve guessed it, building outdoor garden ovens. Watch out for it in your local shops or download a copy: http://www.deliciousmagazine.co.uk/

My second bit of exciting news is that I am about to publish a new book. It’ll be called The Garden Oven Cookbook and will contain lots of amazing recipes and tips for anyone who wants to cook incredible food in an outdoor oven. I’m hoping to get the book self-published, like my building guide, in July. Watch this space for more information.

Finally, I have been thinking for a while about selling outdoor oven related paraphernalia on my website; things like pizza peels, oven thermometers etc. I’m still thinking about it but would like to know your thoughts. If I do, I’ll definitely sell them for much cheaper than you can get them elsewhere. Let me know if you’d be interested by clicking on the poll below.

While the rain continues unabated here in the UK, with no sign of sunshine on the horizon, I have decided to add a few posts which feature ovens from fans of the blog (and who have used, to some degree, my instructions to build their own). What I love more than anything is seeing how other people interpret the original design I posted – and end up with incredible looking creations of their own.

I’m kicking off with a really lovely, rustic looking oven built by Andrew Frazer who hails from Austin, Texas. Andrew came across the blog last year and ended up building his oven in July 2013. Luckily, Andrew has also provided an excellent narrative about the build process and some of the things that influenced the choices he made during the build. I’ll let him continue in his own words.

Click for full-size

My oven was built, this July, with the nearly pure clay that I struck about 18″ under the topsoil and the base is made from limestone rocks that I struck about 4″ under the topsoil! My earlier attempts to dig a garden and plant a couple of trees provided me with all of the free-stacked rocks that form the base. The oven sits on a 3-foot stack of limestone, in-filled with gravel. The oven is clay-dirt from my backyard, mixed about 3:2 or 2:1 with sand from the hardware store. The outer layers have added straw and the final clay plaster is 2 parts sand to 1 part clay dirt. The interior dimensions are 24″ circumference and 16″ high. Fires nicely and holds heat like a dream. Walls are very thick, I’d say 6-8″ in total.

The floor is not bricks but unglazed clay saltillo tiles. They have cracked heavily inside from the heat but are now pretty stable. My next oven will use bricks on the floor for sure. Under the tiles, I insulated with pearlite and clay slip mixed to about “rice krispie treat” consistency.

The oven was built up in this order:

6″ of drainage gravel under the first of the limestone rocks. The rocks are all from my backyard and stacked without mortar.

The interior of the base is filled with urbanite I found dumped in the woods behind my house (a bit of enviro-cleaning) and levelled with pea gravel. This gravel helps to lock everything in place.

Since my rock base was very irregular on the top, it is capped with an inch or two of cob.

The next layer is a pearlite/clay insulating layer. I used a ring of bricks as a dam to hold the insulating layer in place until it dried. The bricks were removed and some were used in the construction of the arch .

The top layer is a 3-4″ thermal layer of clay/sand and finally levelled with dry sand before laying the tiles.

I stacked the rocks such that they would fall “inward” if shifted, so they end up holding each other up without mortar. I did pack some cob in between some rocks that wiggled a bit to stabilize them. This is my first oven and if it was a failure I wanted a way to quickly dismantle it.

I added the wood storage “garage” in November. It is made of a large terra-cotta planter which was destined for trash day when the bottom broke off. I set it on a pile of rocks and locked it in place with cob. I used a few saltillo tiles to form flat shelves that have already come in handy on cooking days. My neighbor says its starting to look like Jabba the Hut. I’m going to help them make their own oven in a couple weeks.

My oven is in Austin, TX and we don’t get many days of rain, but when it comes, it comes in torrents. For now, I wrap it in a tarp (it’s “raincoat”) when the clouds are ominous.

I use it every other week or so. I expect to use it more in summer when I’m banned from baking bread in the kitchen and thus heating up the house. I’ve cooked the predictable loaves of bread. We do pizzas more often than I thought. One night I made a delicious but overcooked roast beef (watch the temperature!). I’ve baked cookies and apple pies in it and we roast eggplant and cherry tomatoes in the residual heat. The morning-after temperature is often over 100F. I hope to get a small “tuscan grill” custom made for it from a local blacksmith so I can do more meat directly over the coals.

Well it’s an absolute beauty Andrew. Thanks so much for sharing with us. Best wishes and happy baking.

Sad isn’t it? I know what you are thinking – “How did he let that happen?” I’m a truly ashamed. I am a bad oven owner! I have neglected my oven and should be reported to the authorities.

I can partly justify the state of my oven by blaming the weather. We had a terrible winter in the UK- snow, cold temperatures and rain – lots of rain! Unfortunately for a large part of the winter I left my oven, normally protected by a tarpaulin sheet, uncovered. Why? Well I don’t really know why, but I did. Anyway, by the time I did cover it up it was too late. The oven was saturated and much of the outer layer had washed away, leaving piles of sand around the top of the plinth. When I finally removed the covers last month I discovered that the situation was even worse – the brick arch had also collapsed, taking much of the chimney with it. Poor oven.

Rather than get depressed about it, now that the weather has improved a little, it’s time to start thinking about what to do to make it better. There are two options:

knock it down and start again from scratch, or

salvage what I can and repair it.

Having looked carefully at the oven yesterday I have decided that it is salvageable and, with some major work and TLC, can be bought back to it’s former glory, and better. The outer layer is mostly washed-away but the insulation layer is 98% intact while, most importantly, the inside oven layer is pretty solid still (there are a few minor cracks which penetrate through to the insulation layer but these can be patched-up with new mixture).

Brick arch and outer layer removed

Slightly slimmer but on the road ro recovery.

I stripped off the outer layer (what was remaining came off very easily without damaging the insulation layer) and removed the brick arch. Over the coming weeks I will do the following:

build a new arch (a friend is designing a “perfect” arch for me using CAD which will involve cutting the bricks to size).

install a pre-made, clay-pipe chimney which will be much more robust than the old one

I’ll be sure to update you with progress and post lots of photos of the re-development.

To borrow a quote from the Six Million Dollar Man, “Gentlemen, we can rebuild him. We have the technology. We have the capability to build the world’s first bionic man. Steve Austin will be that man. Better than he was before. Better, stronger, faster.” I can’t guarantee a bionic oven, or even that it’ll be faster, but I hope it will be at least better and stronger than the previous one. I shall redeem myself. Watch this space.

“All right, but apart from the sanitation, medicine, education, wine, public order, irrigation, roads, the fresh water system and public health, what have the Romans ever done for us?“. So the quote goes from Monty Python’s Life Of Brian. To that list you can also add Clay Ovens. No, honestly! The Roman’s built and cooked in clay ovens and, in common with most of their innovations, they conducted experiments in order to perfect the process of construction. Luckily for us, they also wrote it down!

Sometime between 70 and 15 BC, Roman architect Vitruvius, recorded the shape and proportions of the ovens in use during the 1st century BC. The most important measurement he recoded was that of the height and width of the oven entrance. This happens to be one of the questions I get asked most on this blog so I thought it was time to pass on Vitruvius’s wisdom to you all. I’m happy to say that it is very straightforward, here it is:

The height of a wood-fired oven entrance should be 63 percent of the height of the inside dome. The width of the door should be half that of the oven diameter.

Got it? So, all you need to do is make a note of the height of your sand former during construction and multiply that measurement by 0.63, for the entrance height, and obviously just divide it by 2 for the entrance width. Simple!

But why is this proportion so important? What does fire need in order to burn? A fuel source and oxygen, right? (Yes Simon we knew that. We are not idiots you know!). OK OK! So, When the oven entrance is just the right size it is able to draw in oxygen from the entrance where it combusts, flows around the curved roof of the oven, after which the exhaust gases flow out of the top of the entrance. If the entrance is too small, exhaust gases are prevented from escaping (they mix turbulently with incoming oxygen), they pool in the oven roof and will eventually extinguish the fire. Too large and the oven will be inefficient, losing lots of valuable heat through the gaping entrance.

A 1684 depiction of Vitruvius (right) presenting De Architectura to Augustus (from Wikipedia)

The design I propose on this blog, with a chimney at the front of the oven, just behind the entrance, will help to alleviate many of the problems described above. However, it is still crucial that the entrance is the correct size in order that the oven burns as efficiently as possible.

There you have it! Next time you are firing your oven, think about good old Vitruvius scribing these instructions for future generations to use. I reckon he deserves a toast, don’t you? Cheers!

This weekend I received photos two new oven photos from visitors to the blog. I was struck, in both cases, by how perfect they looked – very neat and tidy. Here are a couple of photos of the ovens, the first is from Dave Slater from Belmont in Surrey (UK), followed by Lisbeth Schelling’s (and family) from Tønder, Denmark.

Dave Slater’s Oven

Family Schillig’s Oven

I was particularly struck by the perfect brick entrance arches to both of these ovens. It seems the secret is to use a template or former around which the bricks for the arch are laid. This is a great idea and one which has been around for centuries, ever since people have been building arches.

Making a former is very straight forward. Just decide on the width of the oven entrance – this will be the the diameter of your former semi circle. Draw it on some flat wood board, such as MDF. Cut it out and then use this to make an exact copy of the first. You then simply connect both semi circles together with connecting pieces, the same length as one of your house bricks. Once constructed, pop it in place in front of your oven entrance and build your bricks around it. Once your arch is complete, pull the former out and, hopefully the arch will stay in place.

Have a look below at more photos from Dave and Lisbeth which demonstrate what I have described.

Thanks to both of them for sharing with us.

Dave’s former in place. You can see the simple construction.

Dave has drawn the brick locations on his former so that the arch is symmetrical.